1. Field of the Invention
The present invention relates to a sheet sorter capable of sorting and collating in plural storage bins sheet members ejected in succession from a recording apparatus such as a laser beam printer or a copier after image formation therein, and capable of being connected in series.
2. Description of the Prior Art
In the conventional sorter or collator for sorting recording sheet members into plural storage bins to obtain identically sorted sets of sheets, it is possible to store the sheet members sequentially supplied from the copier into the first bin located at the most upstream position in the transport path, then into the second bin and down to the n-th bin in successive manner. After the completion of n copies, the original has to be replaced for the next n copies to provide an inevitably wider space between the sheet stored in the n-th bin and the sheet to be subsequently stored in the first bin, and this fact avoids the inconvenience of arrival of the sheet at the first bin before the preceding sheet is stored in the n-th bin.
Consequently such sorter can employ a successive control for the sorting sheets into the bins, with a simple control mechanism.
In case the number of bins in each softer is not sufficient there are employed plural sorters connected in series, and, if the sheets are jammed in one of such sorters, the sorting operation is interrupted only in the sorter having caused such jamming.
However, for certain recording apparatus such as high-speed copier or laser beam printer required is random access of the sheets to the storage bins.
Also in such recording apparatus the above-mentioned jam handling process does not pose problem in the sorters downstream of the jammed sorter since the sheets eventually in transport at the jamming may thereafter be sorted into the storage bins without causing errors in the collating order. However in the sorters upstream of the jammed sorter, the sheets present therein and destined to those sorters are sorted regardless of the jamming. The removal of sheets in case of such jamming is easy if they remain in the transport path in the sorters but is quite difficult once they are stored in the bins. For example in case of a recording apparatus for printing the information from a computer, such as the laser beam printer, the operator is unable to known the page currently printed, and is unable to know the bins in which the sheets are stored after the jamming because of the often random access of the sheets of the bins. Also if the sheets transported in the sorters after the jamming are not removed before the restart of printing, there will result overlapping pages in certain bins since the printing operation is restarted from the point of jamming.